Rust-resisting can



Patented Dec. 11, 1928.

HARRIS, or sar :BANcIsco, CALIFORNIA.

a sr-nEsIs'rmG can. Y

Nonrawin'g.

This invention relates to the so-called tin cans as used for the p'reservingof food products, and more-specificall to'the preparation of theIlltal of which the can ismade 5 whereby it will better resist rusting or other corrosive action either from within the can from, the action of food contents or from" without. T n'cans as at present used are made from tinned sheet iron-,-.and'as is well known are ward appearance of the can so that it is no among which subject to rusting through the coating of tin, either inside or outside of the can,'in the first case resulting in spoilage of the food contents and in. the second destroying the outlonger salable.

To overcome this weakness of tin plate" recourse is sometimes had to lacquering the cans both inside andoutside with an attempt 20 to prevent rusting influence from attacking the'iron through the pores or thin places of the tin coating. v

Such lacquering has its advantages over the plain tin coating but also its drawbacks is the expense and special equipment required for the work, the imparting of'a slight flavor to the preserved prod-I ucts. and the chipping of the lacquer on the outside of the cans with consequent ruining of its appearance and also making it susceptible to rusting through the .tin coating in these places. L

My invention which overcomes the faults of tin plate above outlined yet preserves the natural appearance of the can as demanded v made from sheet iron by the buyer, as well as the resistant features of a tin coating as an external covering consists in making the cans of tinned sheet iron or steel which prior to tinning is rendered 40 substantially rustproof.

By substantially rust proof I mean by coating the sheet with a heavy film of carburet of iron, or combination of oxide and silicate as in Russia iron, or. the heavily blued coatingas in plainshed iron, or the rust res sisting coatings known variously as Parker- .izing. etc., or those produced by treatment of the metal with antimony andferric chloride.

A fter thus rendering the sheet substantlal- Applicatiom'filed December 21, 1925. Serial No. 76,895.

1y rust proof preferably on both sides, I coatthe same on both sides with tin.

The tin coating may be deposited either electrically, chemically or. by the dipping" roce s's suitabl modified in some instances to suit the nature of the rust proof coating which is to be'covered. v 1 -A-can.made. of metal coated as above presents the ordinary appearance of bright tin,

possesses its resistance to "corroding influences and in addition the protection of the underlying-rust'proof coating so that influences which might ordinarily penetrate the tin and corrode. the iron to the disruption of the tin coating, would have little or no efi'ect.-

Also,- in case of mechanical abrasion of the tinned surface the under-coating if of hard oxide nature would still be'intact to prevent rusting of the metal, and in the forming of cahs from such material thenatural softness of the outer tin coating insures freedom from crack'salon the crimped edges which might with more brittle coatings form the nucleus .for corrosive action.

In contemplating the above disclosure it should be noted that while my invention relates principally to the production of tin cans forfood preservation, it may have other uses' such-for instance as the production of rust proof roofing sheet by the terne plate coating of such pre-surfaced metal or of galvanizing the same either electrolytically or otherwise.

I therefore claim 1. As an article of manufacture a can rovided-with a contacting coating of blac compound metallic oxide, andan adherent metallic tin coating on top of the oxide coating.

' 2. The method of protecting iron and i I which comprises chemical treatment of the same to produce a black continuous hard film of rust resistant oxide thereon and covering said oxidecoatin with a film of adherent relatively easily usibl'e metal.

'3 'Iron provided with a contacting coating of a compound metallic oxide and an adherent metallic tin coating thereover. I

NEAL HARRIS. 

